Circuit control for electric flatirons and connection therefor



1943- L. v. LUCIA I 2,307,052

CIRCUIT CONTROL FOR ELECTRIC FLATIRONS AND CONNECTION THEREFOR FiledAug. 25, 1940 IN VEN TOR.

Patented Jan. 5, 1943 I CIRCUIT CONTROL F IRONS AND CONNE Louis V.Lucia, West Hart The Sllex Company, ration of Connecticut OR ELECTRICFLAT- CT'ION THEREFOR ford, Conn., assignor to Hartford, Conn., a corpo-Application August 23, 1940, Serial No. 353,908

11 Claims.

This invention relates to circuit control for electric flat irons andconnection therefor, and is particularly intended for steaming andpressing irons as shown and described in the co-pending application ofFrank E. Wolcott, Ser. No. 337,279, filed May 25, 1940, and assigned tothe assignee hereto.

In devices of this type, it is very important that the temperaturethereof be maintained within a variation of only a few degrees of theoperating temperature which is desired, and that the thermostatic devicefor maintaining said temperature be so constructed that it will notbecome affected, under such conditions as when exposed to a hightemperature in the said device, and will in sure stability in theoperation of the said device.

The object of the invention, therefore, is to provide a highly efficientcircuit control of the thermostatic type for selectively maintaining adesired temperature in a pressing iron.

A further object of the invention is to provide a novel electricalconnection for the heating element of a pressing iron, which is highlydesirable in the use of such irons as well as in the manufacturethereof. 1

Further objects of the invention will be more clearly understood fromthe following description and from the accompanying drawing in which:

Fig. 1 is a side view, partly in central vertical section, illustratingmy invention as embodied in an electric pressing iron.

Fig. 2 is a plan view of the said iron with parts thereof omitted toshow the control embodied in my invention.

Fig. 3 is a side view in vertical section on line 33.of Fig. 4 showingthe construction of said control and its connection in an electricalcircuit.

Fig. 4 is a plan view thereof.

As illustrated in the drawing, the numeral! denotes the casing, or body,of a pressing iron having a sole plate 6 and a handle 1.

In the construction shown, a cover plate 8 may be provided for sealingthe water-heating chamber 9, within the casing 5, and the said cover mayhave projections, such as In, extending therefrom for securing thehandle 1 thereto. 7

The cover 8 may be extended beyond the back of the casing so as toprovide in said iron a control chamber it within which my improvedcircuit control may be contained so that it will not be subjected to thehigh heat to which thermostatic controls for such iron have heretoforebeensubjected in order that sufficiently accurate respons from suchcontrols to the temperature of the sole plate may be obtained.

My improved control, as shown, for controlling anelectric circuit whichsupplies current to a heating element 6a for heating the sole plate and.water chamber 9, comprises an upright frame i2 which is mounted upon theupper surface of the sole plate 6 upon a surface that is adapted tosupport said plate in a slanted position to conform with the design ofthe particular iron illustrated.

An electrical contact member i3, electrically connected to the frame I2,is carried upon a shaft l4 that is rotatable in said frame and has ahead IS, with a flat i 6, to which is secured an operating knob H, withan indicating pointer I8 thereof, for rotating said shaft to positionthe contact cam i 3 for the degree of heat required.

A spring bar 19 issecured to the bottom of said frame It by means of asupporting bar 20 which is insulated from said frame by mica plates 2|;the plate 22 insulating the entire assembly from the sol plate 6, andthe said frame, supporting bar and insulating plates all being securedinto a complete'unit by means of eyelets 23 through which extend thescrews 24 that are threaded into the sole plate 6 for securing the frameI2 thereto.

The spring bar 1 9 is provided with a contact point 25 for engaging thecontact cam l3 and also with a laterally extending arm 28 to which isthreaded an adjusting screw 21 having an insulating point 28 in contactwith a bi-metal bar 29 that is secured directly to the sole plate 6 andoperates in response to the temperature thereof as will be hereinaftermore fully described.

My invention also includes an electrical connection for saidcontrolwhereby electrical conductors, including a wire 30 which is connected tothe frame I 2, and a wire 32, which is connected to the lead wire 6--bof the heating element 6a, extend from said control through an opening33 in the cover 8 into a compartment 34 in the handle 1, and therefrom,through an opening 35 in the back of said handle to the exterior of theiron so that said wires, which may be included in a cord 36, may beconnected to an electrical outlet.

The lead wire 6-0, at the opposite side of the heating element, may beconnected to an extension 3| on the bar 20 which is electricallyconnected to the spring bar l9.

If desired, a sleeve 31 may enclose said cord adjacent to said handle,in order to relieve the cord of undue strain, and the said sleeve may besecured to the handle by means of a head 39 which forms a head engagingthe peripheral portion of 011117, the knob l1 the opening 35 in thehandle. A strain relief 39-41 may also be attached to said cord toengage the surface of the head 39 and thereby anchoring said cord to theiron so as to prevent strain at the points where the wires 3| and 32 areconnected to the control within the chamber H.

In the embodiment illustrated, the handle 1 is preferably constructed oftwo halves which are secured to the member ID by screws 40 and retainedin rigid position by dowels 4|, so as to facilitate the manufacture ofsaid handle as well as the assembling of the above described connectionwithin the chamber 34.

In the operation of my improved control, the knob I1 is first rotated tothe desired position, which may be selected from the indicia on theplate 42 by pointing thereto with the pointer 8. The adjustment of saidknob will rotate the con- I3 so that it will engage the contact point25, thereby closing the electric circuit through the heating element andthus causing said element to become energized and heat the sole plate 6of the iron. This will flex the bimetal bar in an upwardly directionuntil it'engagesthe point 28 of the screw 21 and thereby,

u when the said sole plate has reached the proper temperature, flex thespring bar ii! in a direction away from the contact i3 so as to separatethe contact 25 therefrom and break the electrical circuit through theheating element.

Upon cooling of the said plate to an extent, the said bi-metal member 29will flex in a downwardly direction and permit the contact 25 to againengage the contact [3 and thereby close the electric circuit; thuscontrolling the energizing of the heating element in response to theactual temperature in the sole plate 6 of the iron.

When it is desired to manually break the cirmay be turned in acounterclockwise direction, to an off position indicated on the plate32, wherein the contact l3 will be positioned relative to the contact 25with the flat 42 thereon providing a space between said contact members;it being of course understood that upon the turning of the knob I! tothe desired temperature the said fiat will be rotated so that thecircuit will be closed by engagement between the contact members.

From the above description it will be clearly seen that I have provideda thermostatic control which may be located in a portion of a flat ironwherein there is a lower degree of heat than in the sole plate itselfand which, due to the novel elements and construction of said control,the same will be responsive to the temperature in the sole plate in ahighly sensitive manner; thereby assuring longer life for said controlthan is possible to attain where controls are mounted between the bottomof the iron and the sole plate, or in other close relation to said soleplate, so as to obtain accurate response to variations in temperaturetherein, as commonly done in conventional forms of thermostaticallycontrolled pressing irons.

It will further be seen that I have provided novel means whereby acontrol including parts, of such as spring metal, which aresubject todistortion by repeated subjection to high temperatures, may bepositioned in a portion of a device where they are exposed to a lowertemperature than the actual operating temperature of said device and sothat it may still be operated by a heat responsive member that is inoperating portions It is to be understood of the device.

that, while I have shown close heating relation with the 1 pressing ironsuch as shown, the same may be used in various other types ofelectrically heated devices without departing from the scope thereof asset forth in the appended claims.

I claim:

1. An electric circuit control comprising a frame, a cam-shaped contactmember rotatably mounted in said frame, a resilient member secured tosaid frame and insulated therefrom, a second contact member on saidresilient member, a lateral extension on said resilient member, andadjustable means on said extension engaging a thermally responsivemember to operate said resilient member and thereby move the second con-5 tact member with relation to the rotatable contact member in responseto variations in temperatures affecting said thermally responsivemember.

2. For an electric heating device, a circuit control comprising a framehaving a cam-shaped contact member rotatable therein, a plate secured tosaid frame by means of eyelets and insulated therefrom, a resilient barsecured to said plate, screws projecting through said eyelets for 5securing said control to said device, a bi-metallic thermally responsivebar removed from said frame and secured directly to said device, andmeans ineluding an extension on said resilient bar op-- -erable by saidbi-metallic bar for actuating the same.

3. An electric circuit control comprising a frame having a rotatablecontact member therein, a movable bar in said frame, means secured insaid frame and insulated therefrom'for supporting said 5 movable bar,electric connection means on said bar supporting means, electricconnection means on said frame, a thermally responsive member removedfrom said frame, a lateral extension on said bar, and adjustable meanson said extension engageable with said thermally responsive member forthe operation of said bar by said thermally responsive member.

' 4. An electric circuit control comprising a frame having a rotatableshaft mounted therein,

a cam-shaped contact member on said shaft,

spacing means on said shaft at one side of the contact member andbetween said contact member and frame, spring means at the opposite sideof and urging said contact member and spacing means in the direction ofsaid frame to frictionally retain said cam-shaped member in adjustedposition, a separate contact member engageable with said cam-shapedmember, and thermally responsive means for operating said contact memberrelative to the cam-shaped member.

5. For a device including a heated member, a circuit control comprisingan upright U-shaped frame mounted to said member and insulatedtherefrom, a resilient bar secured to said frame and insulatedtherefrom, an electric contact carried by said bar, a rotatable shaftmounted in said frame, a cam-shaped contact member carried on said shaftwithin said frame, friction means between a side of said frame and saidcam-shaped member for retaining said member in adjusted position, anextension on said bar, an adjusting screw in said extension, aninsulating member in said screw, and a bi-metallic member in directheating relation with said heated member and engaging said insulatingmember foractuating said bar to move the contact thereon with relationto the cam-shaped member in response to variations in temperature insaid device.

6. For an electric heating device, including a and described myinvention as embodied in a heated membenan electric control comprisinganupright U-shaped frame insulated from said member, resilient bar securedto and insulated from the bottom of said frame and extending upwardlytherein between the sides of said frame, an electric contact on saidbar, a cam-shaped contact member rotatably mounted in and adjacent thetop of said frame and disposed between the sides thereof in proximity tothe contact on said bar, a thermally responsive member removed frominsulated therefrom, an electric contact on said bar, a rotatablecam-shaped contact member between the said extensions and adjacent tothe contact member on said bar, a thermally responsive member, and anextension on said bar between the contact member thereon and said baseand in position to be engaged by said thermally responsive member tooperate said bar.

10.- An electric circuit control of the character said frame and indirect contact with said heateddescribed comprising a frame including abase member, and an extension on said bar having adjustable means incontact with said thermally responsive member for operating said bar andmoving the contact thereon relative to the cam having parallelextensions thereon, a resilient bar mounted on said base and insulatedtherefrom, an electric contact on said bar, a shaft rotatable in saidframe, a cam-shaped contact member on shaped contact member in responseto tempersaid shaft and disposed between said parallel exature changesin said heated member.

'7. For an electric heating device, a circuit control comprisin anupright frame, a resilient bar secured to said frame and insulatedtherefrom,

tensions, electric conducting spacing means between said cam-shapedmember and frame, spring means between said frame and camshaped memberurging said member in the dian electric contact on said bar, acam-shaped rection of said spacing means and frame, and a contactrotatable in said frame, thermally responsive means responsive totemperature changes in said device for actuating said bar, a

lateral extension on said bar, and adjustable means betweensaidextension and thermally responsive means.

8. An electric circuit control comprising a 7 frame including'a basehaving parallel portions extending therefrom, a resilient bar mounted tothe base of said frame and insulated'therefrom,

a contact carriedby said bar, a cam-shaped contact member rotatablymounted in said frame and disposed between said parellel portions inproximity to the contact member on said bar, a

said frame, and means extending from said bar and contacting saidthermally responsive member for moving the contact on said bar withrelation to said rotatable cam-shaped member.

thermostatic bar for operating said resilient bar.

11. For an electrically heated device, a circuit control of thecharacter described comprising an upright U-shaped frame, a shaftextending diagonally to and rotatably mounted in said frame, acam-shaped contact member carried by said shaft and disposed centrallyin said frame between the sides thereof, a bar mounted to the base ofsaid frame and extending upwardly therefrom between the sides of saidframe and adapted to contact with said cam-shaped member, a bracketsecured to said movable bar at a distance from said base and extendinglaterally therefrom, a thermally responsive member rethermallyresponsive member separated from 5 9. An electric circuit controlcomprising a 40 frame including a base having parallel extensionsthereon, a resilient bar mounted to said base and moved from said frameand responsive to temperature changes in said device, adjustable meansbetween said bracket and thermally responsive member for transmitingmovement from said member to said bar, and electrical connecting meanson said frame and bar.

LOUIS V. LUCIA.

